Fix the subject check of Batch attestation

- By getSubjectDN().getName() we'll have OID only
- Root cert doesn't have "StrongBox" in subject

Bug: 152343104
Test: atest CtsKeystoreTestCases:android.keystore.cts.KeyAttestationTest#*-- --abi arm64-v8a
Change-Id: Iebd5cda50b695c8fa97ec3bb8a2be9d123646283
1 file changed